Shoe-nail.



G. A. CURTIS.

SHOE NAIL.

' APPLICATION FILED NOV. 14, 1911, 1,033,159. ,Patented July 23, 1912.

wi'hzeasea Qlhvenlorf attdEl ia w 4 of Medford, in the State ofMassachusetts, tain new U STATES PATENT GFFICE.

GEORGE A. CURTIS, 0F MEDFORD, MASSACHUSETTS.

SHOE-NAIL.

a shoe nail having an improved form oftapering portion having a lesstendency to cripple While driving than the ordinary nail now in use, andwhich portion is longer, relatively to the length of the shank portion,than usual, resulting in advantageshereinafter described.

A further object is the provision of such av nail having a formationthat will present no anglealong the inner curve of the' clenched end tobear on the surface of the work held by such clenchedend. To these endsthe invention consists in-the nail substantially as hereinafterdescribed and claimed.

Of the accompanying drawings,-Figures 1 and 2 are side elevations of twoofiny improved nails, one being straight and the other showing theresult of the clenching operation. line 33 of Fig.1. Fig.4 represents'asec} tion on line 4 4 of Fig. 1. Fig. 5 represents a section on line ofFig. 1.

Similar reference characters indieate'the same or similar parts in allof the views.

The round and transversely notched shank a and head b mayb as indicated,according,

to a well known form of shoe nail; but the tapering portlon is longer,relatively to the length of the shank, than usual, this greater lengthbeing possible due to the novel form of said tapering portidn. aspresently described. Said tapering portion is formed with four flatsides 0, c, c, c, which meet each.

other at a righting-lo said flat sides being en'uctlyalike and equaltofea h other and straight- 130111 'wl'iere they join the round shank ption at d to a slightly rounded tip e, so that. a transverse section oneither of the lines 3.. l or 5 of Fig. 1, or between those line will insquare as illustrated in Figs. 3, e ant 5. it will now be understoodthat if the tape ing portion were sou'iewhat {lattened to oral orrhomboidal form, and still made as long shown in F igi 1, the stockSpecification of Letters Patent. Application filed November 14, 1911.Serial No. 660,238.

'flat sides.

Fig. 3 represents a section on Patented July 23', 1912.

would be so thin at intermediate points,

especially from line 4 to line 5, that the nail would be liable tocripple when being driven; in other words, to bend and go crooked beforegetting through the work.

But owing to --my improved structure of square cross section from endto, end of the taper, the said taper can extend unusually far up fromthe tip and still'leave suflicient thickness of stock to insure straightdriving,

as seen by reference to Figs. 4 and 5. Thjs increased length 'oftaper;increases the length of the portion of the nail which is capable ofbeing curled up by the usual clenching operation, and therefore thereneed be less careful selection of lengthv of nails to suitparticulargthicknesses of Work.

In other words, 'one lengthof nail can be' used for a greater variety ofthicknesses of work. Another advantage is that when the Y nail clenched,it practically invariably curls in a plane parallel with two parallel Inother Words, it curls, as shown inqFig. 2, with one. fiat side a formingthe inside of thelcurl. This "is because the greater thickness on a lineintersecting the center and two angles resists curling in such directionas to bring an angle inside the curl. Therefore, although the nail maycurl in eitherone of four directions, it wi l be practically certain toso curl that a flatside will bear .onthe surface of the work throughwhich the nail is driven and against which surface the inside of thecurl bears, and con sequently the inside of the curlwill present noangular rib to cut into the Work.

I claim A shoe nail having a tapered portion square in cross section andpresenting four 'liat sides which converge toward'the tip,

said tip being rounded, all four cornersv or angles between said flatsides also converg-' ing toward the tip, whereby said-tapered portionwill possess the same square cross sectional shape at differentdistances from the tip but gradually of less cross sectional area towardtheti'p. v I

In testimony whereof-1 have Rflixed my signature, in presence of twowitnesses.

GEORGE A. CURTIS.

Witnesses:

A. 7. HARRISON, P. W. Pnzzn'r'ri.

Washington, D. G.

addressing the Commissioner's? Patents,

